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Michigan Avenue BioretentionMonitoring the Results 3 Years Later

MWEA 86th Annual Conference, June 28, 2011Dan Christian, P.E., D.WRE Tetra Tech

Valerie Novaes, Tetra Tech

Native Plant Nursery

Virg Bernero, MayorVirg Bernero, Mayor

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Agenda

• Project Overview• Soils: infiltration, porosity, field capacity• Plants: overall health and planting plans• Monitoring• Modeling• Challenges and Lessons Learned• Future Applications

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Bioretention Area

Penn

sylv

ania

Ave

nue

Larc

h St

reet

Michigan Avenue

Grand River

Sparrow Hospital

Oldsmobile Park

State Capitol

City Hall

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Design• Ultra-Urban• 5-ft wide planter box

style bioretention– 30 bioretention gardens– 7,631 square feet– 4.1 acre tributary area

• 4 blocks, both sides• ADA compliant• Adaptable to community

needs

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Construction 2007 to 2008

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Final Product

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Construction CostsRetaining Wall $22 / sfPlants and Watering $4.25 / sfEngineered Soil $27 / cyPeastone (washed) $40 / cyTop Mulch $42 / cySediment Forebay $1700 eachMetal Plates $1.40 / lb

• Bid: $1,000,000*

• $122/SF (Ultra-urban)

• $30/SF (Without urban constraints)

* As this was part of a larger project, the total bid cost is an estimated portion of the whole.

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Soil Porosity and Field Capacity

• Question– What is the volume available in the soil to temporarily

store stormwater?– Is there a correlation between the unfilled pore space

and the plant health?• Methods

– Soil analysis for bulk density, porosity and field capacity– Correlate analysis results with overall plant health

assessment

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Soils

• 30% Sand (MDOT 2NS)• 30% Topsoil

– 10% sand– 40% silt– 40% clay– 10% organics

• 10% Coconut coir fiber• 30% Municipal compost (aged 12 months)

Total clay content 12%

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Soil AnalysisBioretention Garden

Location within the

garden

Bulk Density (g/cm3)

Porosity (%) Field Capacity (%)

Temporary Storage

(Porosity – FC) (%)

700 blocksouth side (#33)

East 1.06 52.4% 31.3% 21.1%

Center 1.18 48.6% 29.7% 18.9%

West 1.20 43.2% 27.5% 15.7%

800 block south side (#43)

East 1.17 49.2% 25.8% 24.5%

Center 1.25 46.5% 25.8% 20.7%

West 1.29 45.7% 25.8% 19.9%

700 block north side (#14)

East 1.08 57.8% 27.9% 29.8%

Center 0.89 62.5% 40.5% 22.1%

West 1.05 49.2% 31.6% 17.6%

Average 1.13 50.6% 29.5% 21.0%

* Non-compacted soil

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Bulk Density

Measured

Limiting

Urban, James. Up by Roots: Healthy Soils and Trees in the Built Environment. 2008

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Water Holding Capacity

21%

FISRWG. Stream Corridor Restoration: Principles, Processes, and Practices. 2001.

50.6% porosity measured

29.5% field capacity measured

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Infiltration• Questions

– What is the infiltration capacity of the engineered soils?

– Does the infiltration rate vary based on location within the bioretention garden?

– Comparison of infiltration equipment• Methods and Equipment

– 24-inch double-ring; LID Manual for Michigan Appendix E

– 4-inch Turf-Tec (www.turf-tec.com); manufacturer instructions

– Mini-disk Infiltrometer (www.decagon.com); manufacturer instructions

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Infiltration

Garden # Location within

Garden

Equip-ment

Date Mulch and top 2-inch

soil

Infil-tration (in/hr)

#33; south side west of Hill St (Young Bros & Daley)

East24-inch

8/13/2010 Removed 8.7

6/1/2011In Place 0.2Removed 0.1

Turf-Tec 6/1/2011In Place 2.2Removed 2.2

Middle

24-inch9/28/2010 Removed 2.9

6/2/2011In Place 1.9Removed 1.2

Turf-Tec9/28/2010 Removed 21.5

6/2/2011In Place 19.9Removed 0.0

Middle-West

24-inch 6/3/2011In Place 14.4Removed 5.3

Turf-Tec 6/3/2011In Place 12.8Removed 4.9

West

24-inch8/13/2010 Removed 7.2

6/3/2011In Place 10.9Removed 1.8

Turf-Tec8/13/2010 Removed 3.6

6/3/2011In Place 6.9Removed 0.0

#14 north side west of Hosmer St (MSHDA) Middle

24-inch 9/27/2010 Removed 4.0Turf-Tec 9/27/2010 Removed 0.6

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0 20 40 60 80 100 120 140 160 180 2000.0

5.0

10.0

15.0

20.0

25.0 East 24-in 8/13/10 mulch removed

East 24-in 6/1/11 mulch in-place

East 24-in 6/1/11 mulch removed

East Turf-Tec 6/1/11 mulch in-place

East Turf-Tec 6/1/11 mulch removed

Middle 24-in 9/28/10 mulch removed

Middle 24-in 6/2/11 mulch in-place

Middle 24-in 6/2/11 mulch removed

Middle Turf-Tec 9/28/10 mulch removed

Middle Turf-Tec 6/2/11 mulch in-place

Middle Turf-Tec 6/2/11 mulch removed

Middle-West 24-in 6/2/11 mulch in-place

Middle-West 24-in 6/3/11 mulch removed

Middle-West Turf-Tec 6/3/11 mulch in-place

Middle-West Turf-Tec 6/3/11 mulch removed

West 24-in 8/13/10 mulch removed

West 24-in 6/3/11 mulch in-place

West 24-in 6/3/11 mulch removed

West Turf-Tec 8/13/10 mulch removed

West Turf-Tec 6/3/11 mulch in-place

West Turf-Tec 6/3/11 mulch removedTime (min)

Infil

trat

ion

(in/h

r) Legend Notes:- Location designated by color- Unit designed by line: 24-inch double-ring solid line Turf-Tec dashed line- Dates designated by marker shape- Mulch designated by marker: removed marker filled in-place marker empty

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Infiltration• Highly Variable• Despite low measured values, gardens

continue to drain well• Mini-disk infiltrometer couldn’t seal

around base• Impractical to test with mulch in place• Suggest

– Larger test area **– Use full bioretention area when possible

** Bouwer, H. Chp 32 Intake Rate: Cylinder Infiltrometer of the Methods of Soil Analysis Part 1, Physical and Mineralogical Methods Second Edition, 1986

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Vertical Drain Installation• July 2009• Observations

– Mulch extremely thick (up to 8-inches)– Clogged geotextile around underdrain

• Vertical drains installed in poorly draining garden– Perforated 4-inch PVC– Surrounded by stone

• Re-inspected in September; working well

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Plant and Garden Health Questions

• What is the overall health of the planted community? • Are there any trends in plant species survival/health? • What is recommended for replanting specific gardens? • Is there any correlation between the following and the health

of the plants: condition of the soil, the thickness of the mulch, the presence of weeds, and the presence of trash/debris?

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Plant and Garden Health Assessment

• Photographs• Quantification of each grass, forb, and

tree species present • Qualitative assessment of each plant

species• Pervasiveness of weeds• Condition of the soil• Degree of erosion• Degree of soil compaction• Thickness of mulch• Pervasiveness of trash/litter• Overall aesthetics

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Plant and Garden Health Results• No immediate action needed on any gardens• Inlets: All good condition; except 1 cracked plate• Weeds: 70% gardens few weeds; 17% excessive• Soils: 20% excessively wet, 80% good• Erosion: no concerns• Compaction: no concerns• Mulch: 73% too much mulch (as thick as 9”)• Fencing: 2 gardens with missing caps, bent rails• Curbing: no problems• Sumps: no problems• Trash/liter: 20% gardens no trash, 17% excessive• Overall aesthetics: 64% good, 21% fair,15% poor

September 2009

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Plant and Garden Health Results

• Overall plant health: 10% fair condition, 90% good

• All species originally used have survived to some degree or thrived in some gardens

• Some of the most salt tolerant species did not fair well

• Perennial replacement– 2009 estimated 530 (16%)– 2011 actual 853 (26%)

Good Performers• Joe-Pye Weed (Eupatorium

maculatum)• Boneset (Eupatorium

perfoliatum)• Rose Mallow (Hibiscus

moscheutos)• Southern Blue Flag (Iris

virginica)• Switch Grass (Panicum

virgatum)• Ironweed (Vernonia missurica)

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Plant Replacement

50% of replacement plants• Species doing very well

– Joe-Pye Weed– Boneset– Rose Mallow– Southern Blue Flag– Switch Grass– Ironweed

50% of replacement plants• Original list

– Nodding Wild Onion– Swamp Milkweed– Tall Tickseed– Alum Root– Giant St. Johns Wort– Rough Blazing Star– Marsh Blazing Star– Beardtongue– Yellow Coneflower– Three Lobed Coneflower– Stiff Goldenrod

• Plus trial plants– Purple Coneflower– Queen of the Prairie– Obedient Plant

Replacement Planting June 2011

Rose Mallow

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Problem Gardens• Several gardens not draining sufficiently to support the originally

selected species• Evidenced by

– absence of the planted species– growth of cattails

• Cattails– Thriving, unique and attractive– Improving overall drainage– Improving dewatering of gardens

• Plan– Leave cattails– Supplement with suitable new species– Tall Sunflower (Helianthus giganteus)– Three-Square (Schoenoplectus pungens (Scirpus americanus))– Softstem Bulrush (Schoenoplectus tabernaemontani (Scirpus validus))

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Hydrograph Modification

– Monitoring• Rainfall• Surrogate site• Bioretention upstream and

downstream• Rainfall simulation tests

– Modeling• EPA SWMM V5.0.021• Pre- conditions based on surrogate site• Post- based on monitored bioretention• Model expanded to 4 block system• Model range of storm events

• Question– How have the bioretention systems modified the surface runoff

hydrograph (volume, Tp, Qp, shape)?

• Methods

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Rainfall Simulation Test• Monitoring period – minimal

events• Simulated Rainfall

– 1.3 inches over 4 hours– 1st quartile Huff distribution

• Fire hydrant / garden hose valves• Excellent results

– Fast– Accurate– Fewer unknowns

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H/H Model• Method

– SWMM 5.0.021• Input measured soil characteristics• Tried different modeling techniques to simulate

the bioretention– Groundwater routine– Traditional storage– New LID options ***

• Calibration– Flow monitoring data– Pre- and Post- bioretention

• Solved for a range of storm events

Example calibration plot

Hydrology Change SummaryRainfall Pre- Condition

(no bioretention)Post- Condition

(with bioretention)Change from

Pre- to Post- Conditions

Recur Interval

Duration(hr)

Total(in)

SRO(in)

Qp(cfs)

Tp(hr)

SRO(in) Qp (cfs) Tp

(hr) SRO (%) Qp (%) Tp(%)

2-month 1 0.52 0.51 0.13 0.17 0.37 0.02 1.08 -27% -87% 535%

6-month 1 0.77 0.76 0.21 0.17 0.61 0.03 1.33 -20% -84% 682%

1-year 1 0.95 0.94 0.27 0.17 0.79 0.04 1.41 -16% -87% 729%

2-year 1 1.14 1.14 0.37 0.17 0.98 0.04 1.41 -14% -89% 729%

10-year 1 1.61 1.61 0.55 0.17 1.44 0.20 0.33 -11% -64% 94%

25-year 1 1.92 1.92 0.66 0.17 1.75 0.29 0.25 -9% -56% 47%

100-year 1 2.44 2.43 0.87 0.17 2.28 0.58 0.20 -6% -33% 18%

2-month 24 1.12 0.92 0.05 12 0.75 0.01 20 -18% -82% 67%

6-month 24 1.64 1.44 0.07 12 1.25 0.01 19 -13% -81% 58%

1-year 24 2.03 1.83 0.10 12 1.62 0.04 13 -11% -56% 8%

2-year 24 2.42 2.22 0.11 12 2.02 0.07 13 -9% -38% 8%

10-year 24 3.43 3.25 0.16 12 3.01 0.10 13 -7% -40% 8%

25-year 24 4.09 3.89 0.19 12 3.66 0.12 13 -6% -38% 8%

100-year 24 5.20 5.00 0.23 12 4.75 0.15 13 -5% -34% 8%

90% 24 0.90 0.70 0.04 12 0.54 0.02 16 -23% -50% 33%

SRO = Surface RunoffQp = Peak FlowTp = Time to Peak

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Runoff Comparison1-year 1-hour

10-year 1-hour

1-year 24-hour

10-year 24-hour

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Hydrograph Modification Results

• Change in runoff as a function of total rainfall

• Decrease in surface runoff• Decrease in observed

peak discharge• Increase in time of

concentration

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Challenges and Lessons Learned• Trash/debris

– Collection– Cigarette butts– Dog poop– Wind blown trash

• Education– Local businesses– Maintenance

• Design-Construction– Plant now, don’t wait– Geotextile– Sidewalk slopes compared to

flat bottom bioretention– Cars hitting the fence

• Monitoring– Low flows– Simulated rainfall event

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Green Plans in Lansing• Boulevard bioswales on Linden Grove Ave

(constructed)• Boulevard infiltration on Barnes Ave

(constructed)• Bioretention swale on Riley St (designed)• Bioretention cells on Bank St (designed)• Bioretention curb extensions on Barnes

Ave and Ray St (designed)• Bioretention curb extensions on

Washington Square (constructed)• Permeable pavement parking lane on

Barnes Ave (constructed)• Permeable pavement parking stall on

South St (designed)

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Thanks and Questions